1+ function findPivotPoint ( arr ) {
2+ let low = 0 ,
3+ high = arr . length - 1 ;
4+ while ( low < high ) {
5+ if ( low == high ) return low ;
6+ let m = parseInt ( ( low + high ) / 2 ) ;
7+ if ( m < high && arr [ m ] > arr [ m + 1 ] ) return m ;
8+ else if ( m > low && arr [ m ] < arr [ m - 1 ] ) return m - 1 ;
9+ else if ( arr [ low ] >= arr [ m ] ) high = m - 1 ;
10+ else low = m + 1 ;
11+ }
12+ return - 1 ;
13+ }
14+ 15+ function searchK ( arr , low , high , k ) {
16+ while ( low <= high ) {
17+ let m = parseInt ( ( low + high ) / 2 ) ;
18+ if ( arr [ m ] == k ) return m ;
19+ else if ( arr [ m ] < k ) low = m + 1 ;
20+ else if ( arr [ m ] > k ) high = m - 1 ;
21+ }
22+ return - 1 ;
23+ }
24+ 25+ function searchInRotatedArray ( arr , k ) {
26+ let pivot = findPivotPoint ( arr )
27+ if ( pivot == - 1 ) return searchK ( arr , 0 , arr . length - 1 , k ) ;
28+ if ( k == arr [ pivot ] ) return pivot ;
29+ if ( k >= arr [ 0 ] && k < arr [ pivot ] ) {
30+ return searchK ( arr , 0 , pivot , k ) ;
31+ } else {
32+ return searchK ( arr , pivot + 1 , arr . length - 1 , k ) ;
33+ }
34+ }
35+ 36+ let arr = [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 30 , 1 , 2 , 3 , 4 , 5 ] ;
37+ let k = 30 ;
38+ let index = searchInRotatedArray ( arr , k ) ;
39+ if ( index == - 1 ) {
40+ console . log ( k + ' not found' ) ;
41+ } else {
42+ console . log ( k + ' found at index ' + index ) ;
43+ }
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